The Prince: Prince Caspian (Ben Barnes), obviously. Though he's been ousted from the throne, and needs the Pevensie kids to help him reclaim it.
Most Heroic Moment: Caspian may look the part, but this is a man who uses an 'enchanted horn' to get help from four schoolkids. That said, he does at least get to prove himself in the final battle between the Narnians and the Telmarines.
If He Was A Villain: He'd probably play up the Spanish accent even more. And there's no way his hair would be that glossy.